Substance in Metaphysics: From Aristotle to Spinoza
The concept of substance has been central to Western metaphysics, evolving through the works of Aristotle, Thomas Aquinas, René Descartes, and Baruch Spinoza. Aristotle first formalized substance (ousia) as a composite of matter (hyle) and form (morphe), rejecting earlier materialist views. Thomas Aquinas adopted Aristotle's definition but added a theological dimension, distinguishing essence from existence and placing God as the supreme substance. Descartes defined substance as that which depends on nothing else for its existence, positing two distinct substances: material (res extensa) and mental (res cogitans), leading to his famous cogito ergo sum. Spinoza countered Descartes by asserting a single substance—God or Nature—with two attributes: thought and extension. Each philosopher's view of substance shaped their understanding of human nature: Aristotle saw humans as rational animals, Aquinas as souls seeking salvation, Descartes as thinking minds, and Spinoza as modes of infinite nature.
Key facts
- Aristotle formalized substance as ousia, a composite of matter (hyle) and form (morphe).
- Thomas Aquinas defined substance as 'that which exists in itself and not in another' in Summa Theologiae.
- Aquinas distinguished essence from existence, with God as the only substance whose essence and existence are identical.
- René Descartes defined substance as 'a thing which exists in such a way as to depend on no other thing for its existence.'
- Descartes posited two substances: res extensa (material) and res cogitans (mental).
- Descartes' cogito ergo sum established the thinking self as indubitable foundation.
- Baruch Spinoza argued for a single substance—God or Nature—with attributes of thought and extension.
- Spinoza's monism rejected Descartes' dualism, uniting mind and matter as attributes of one substance.
Entities
Artists
- Aristotle
- Thomas Aquinas
- René Descartes
- Baruch Spinoza